1. Field
The present invention relates to titanium and other metal parts. More particularly, the invention relates to a system and method for direct manufacturing of and providing stress relief to metal parts for aircrafts and other applications.
2. Related Art
Electron beam (EB) direct manufacturing is a process for making titanium parts and other metal parts for aircrafts and other applications. In EB direct manufacturing, a metal wire is deposited onto a metal plate and an electron beam bombards the wire as it is deposited onto the metal plate within a vacuumed chamber. The electron beam provides a focused heat to the metal wire for melting and deposition of the metal wire, bonding the metal wire to the metal plate and preceding metal wire layers. The electron beam transfers heat to the metal wire via conduction and/or radiation. Direct manufacturing is sometimes alternatively referred to as additive manufacturing, metal rapid prototyping, electron beam additive manufacturing, electron beam free form fabrication, or solid free form fabrication.
Because of the difference in temperatures of the metal plate and the metal wire heated by electron beam, stress may form within the metal part, such as warping, distortion, cracking, and other stresses introduced to the part during deposition of the metal wire. To relieve these intermediate stresses, the deposition process is stopped, the metal part is removed from the vacuumed chamber, and the metal part is sent off site to a qualified heat treat facility to stress relieve the metal part. Once the metal part receives stress relief treatment, it is shipped back to the manufacturer to be reinserted into the chamber, vacuumed again by the proper amount, and then again receives more layers of the metal wire.
Sometimes several rounds of deposition and subsequent heat treatment are required before completing the metal part. The shipping of the part and the use of separate heat treating equipment at a second facility adds to the overall time and cost of manufacturing the metal part using EB direct manufacturing.